Flush valve



c. s. NASMYTH 1,812,301 I FLUSH VALVE June 30, 1931.

Filed Sept. 4, 1929 By his Attorney,

WITNESSES. v #5.

Patented .lune 30, 1931 J NETED STATES PATENT QFFE CE CHARLES SYDNEY NASMYTH, OF SYDNEY, NEW SOUTH WALES, AUSTRALIA FLUSH VALVE Application filed September 4,1929. Serial No. 380,403.

The invention relates to what are generciprocable in casing 1 and has upon it a ally known as silent flush valves employed cylinder 7 in which is a piston Va ve 8 adaptfor sanitary purposes and more particularly ed to close acentral passage 9 extending to the class of such valves in which action is through the plunger and through the main 5 set up by the operation and release of a push valve and which is also designed when in its 55 button. normal position to close portways ldat the In such valves it is of importance that lower end o1 cylinder 7. flushing water shall pass only when the push The plunger as illustrated is provided button has been operated and then released with bucket leathers 25 but a plunger t as otherwise it might be possible by continuany usual type may be substituted. 60 one pressure upon the push button, to waste T he valve 1s guided by a tubular spindle a considerable quantity 01" water without pro- 1.1 projecting below it and passing through ducing a suiiicient flow for flushing purposes. ahole in a cross bar 12 in the extension 3. It is also important that approximately the Reciprocable within the upper end of cylsame quantity of flush water shall be disinder 7 is a piston 13 fixed upon a spindle 14- 55 charged notwithstanding differences of prespassing through a packing gland 15 in the sure in the main supply pipes. cover plate 16 and having upon its end a My invention provides a simple flushing pres button 17 sli-dable through the top of a apparatus having the desired characteriscover cap 18 which screws upon the top of 30 tics. casing l and holds the cover plate in posi- According hereto a. main valve closing the tion. A bypass hole 19 passes through the flush pipe is integral with a plunger slidpiston 18.

able in a cylinder, A spiral spring 20 sleeved upon spindle 14: W'ater from the main supply pipe fills the tends to project the press button and to raise cylinder above the plunger and the main the piston 13 to the top of cylinder 7.

valve is kept upon its seat by pressure. A rubber Washer 21 upon spindle 1% reduces hen the pressure above the plunger is shock when the piston rises to the limit of its reduced by means to be hereinafter described stroke.

the pressure below it forces it upwards lift- A small passage 22 in the casing leads from ing the valve from its seat and permitting above plunger 6 to the branch 2 and is proflushing water to flow from the supply pipe vided with an adjusting set screw 23. through the flush pipe. A stud 26 projecting from the cover plate The flushing continues until pressure passes into a hole in the casing and ensures above the plunger is restored by the perthe correct position of the cover plate.

colation of Water through a relatively small A passage 24 leading through the cover 55 portway, the valve then returns to its seat. plate 16 to below valve 5 provides for the I will now describe the details of my indischarge of water which may happen to vention and the operation thereof by aid of escape through the packing gland. the accompanying drawing wherein: In operation pressure upon the press but- 40 Fig. 1 is a central sectional elevation. ton forces the piston 13 into the cylinder 7 Fig. 2, a sectional plan on 2 2 Fig. 1. the water displaced passing through the by 3, a sectional plan on 3 8 Fig. 1 and pass 19. Fig. 4, a sectional plan on 4 4 Fig. 1. Removal of pressure upon the press button The cylindrical casing 1 has the lateral permits the piston to rise in cylinder 7 and branch 2 to which the main water supply the piston valve 8 is lifted by suction from pipe is connected and a cylindrical extenits seat permitting water from above the sion 3 to which is connected the flush pipe 4. plunger 6 to escape through the portways 10 A valve 5 seated upon the top of the eX- and through the passage 9 to the flush pipe. tension closes the passage to the flush pipe. Pressure above the plunger 6 being thereby A plunger 6 integral with valve 5 is re reduced it is forced up by the pressure below 109 it, the valve 5 is lifted from its seat and a rush of flushing Water takes place from the main pipe through the flushing pipe.

Pressure above the plunger 6 is gradually V 6 restored by Water passing through the restricted passage 22 until equilibrium of pressure being re-established above and below the plunger the main valve resumes its seat and the flow of Water ceases.

The period during which the flushing continues depends upon the area of the passage 22 and this may be regulated as desired by the set screw 23. V

I claim:

1. Flushing apparatus comprising in combination a cylindrical casing, a plunger reciprocable therein, a valve connected to the plunger adapted to close the opening to a flush pipe, a cylinder connected to the plunger provided With'portWays, a piston valve Within the cylinder adapted to close a passage through the plunger and also the portvvays in the cylinder, a piston reciprocable within the cylinder and having a bypass passage, a rod to Which the piston is connected, a push button upon the end of the rod, and a spring sleeved upon the rod, the casing having a passage Way extending from above the plunger to the main Water supply pipe substantially as and for the purpose specified herein and illustrated; V

2. In flushing apparatus such as claimed in claim 1 the combination of a plunger, a valve connected thereto adapted to close a 5 flush pipe, a cylinder upon the plunger, a piston valve 'reciproc-able therein adapted to close portWays in the cylinder and also a passage through the plunger and the valve, a piston reciprocable'vvithin the cylinder and 40 having a bypass passage, spring means for returning the piston to its normal position, and means by Which the piston is forced into the cylinder substantially as and for the purpose herein described and illustrated.

In testimony whereof have signed my name tothis specification. 7

CHARLES SYDNEY NASMYTH. 

